This invention relates to a method and apparatus for supplying electrical energy to an electrostatic precipitator. More particularly, this invention relates to a method and apparatus for supplying to an electrostatic precipitator a d-c voltage of variable level and superimposed voltage pulses.
To increase the degree of dust separation achieved by electrostatic precipitators, the electrodes of the precipitators have been subjected to d-c voltages at levels just under the breakdown limits of the precipitator, as well as to high-voltage pulses of variable pulse amplitude, pulse width, pulse repetition frequency and/or pulse rise rate. The high-voltage pulses serve to generate additional charge carriers in the electrostatic precipitators without provoking the formation of arcs. Generally, the high-voltage pulses are generated by exciting the primary winding of a high-voltage transformer having a secondary winding connected to an electrode of an electrostatic precipitator.
Such arrangements for electrically energizing electrostatic precipitators are known from West German Offenlegungsschrift No. 30 27 172 and West German Offenlegungsschrift No. 32 46 057. A method disclosed in the former patent document is aimed at optimizing the separating action with respect to the energy expenditure.
An object of the present invention is to provide a method and apparatus for supplying electrical energy to an electrostatic precipitator which maximizes the dust separation effectuated by the precipitator.